INVESTMENTS - Information Regarding Pretax Realized Gains and Losses From Investments (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Gain (Loss) on Securities [Line Items]
Other-than-temporary impairment losses realized	$ (2)	$ (7)
Loan loss reserves	(2)	(7)
Derivative gains (losses)	0	144
Foreign currency gains (losses)	(2)	(228)
Total realized investment gains (losses)	71	(134)
Loan receivables
Gain (Loss) on Securities [Line Items]
Total realized investment gains (losses)	(2)	(7)
Derivatives and other
Gain (Loss) on Securities [Line Items]
Total realized investment gains (losses)	(2)	(84)
Equity securities
Gain (Loss) on Securities [Line Items]
Total realized investment gains (losses)	58	(46)
Available-for-sale securities \| Fixed maturities
Gain (Loss) on Securities [Line Items]
Gross gains from sales	12	10
Gross losses from sales	(8)	(2)
Foreign currency gains (losses) on sales and redemptions	13	(5)
Total realized investment gains (losses)	$ 17	$ 3

Foreign currency translation gains (losses) on remeasurement of monetary assets

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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Amount of other-than-temporary impairment (OTTI) on investment in debt security, recognized in earnings.

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